Abutment for arches.



No. 776,252. PATENTED NOV. 29, 1904. M. MULLER.

ABUTMENT FOR ARCHIE S.

APPLICATION FILED JULY 6. 1904.

N0 MODEL.

' UNITE STATES;-

MAX MoLLnR, or BRITNSWTCK, GERMANY, ASSIGNOR TO MUESER, or NEW YORK, N.Y.

Patented November 29, 190%.

PATENT OFFICE.

WILLIAM ABUTMENT FOR ARCHES.

v SPECIFIOATIONfOrming part of Letters Patent No. 776,252, datedNovember 29, 1904;.

Application filed July 6, 1904. Serial No. 215,536- NO 111011 1.)

T0 to whom, it may concern.-

Be it known that I, MAX MoLLnR, professor, a subject of the Duke ofBrunswick, Germany, residing atBrunswick, Germany, have invented certainnew and useful Improvements in Abutments for Arches, of which thefollowing is a specification.

My invention relates to abutments for arches; and its novelty consistsin the means employed to counteract the thrust of the arch, as will bemore fully hereinafter pointed out.

In the drawings, Figure 1 represents in vertical section the end of anarch provided with my improved abutment, one member of which isvertical; and Fig. 2 represents a similar View of an arch in which thereis shown my improved abutment with two members at an acute angle to thehorizontal member.

Heretofore arches have been built provided with abutments designed toresist the thrust of the arch along the line of pressure, the abutmentbeing made large and massive enough to accomplish the desired purposeand of a shape commonly trapezoidal or the like, as indicated in dottedoutline at a in Fig. 1, the principle governing the size and location ofthe abutment being that the line of pressure of the arch shall strikethe foundation of the abutment well inside of the middle third of thetotal depth of the latter. Such abutmentsare of necessity large andcostly.

It is the purpose of my invention to diminish the size and lessen theexpense of abutments of this class, and, in brief, I accomplish it bymaking the abutments of two members the axes of which shall coincidesubstantially with horizontal and vertical lines of which the line ofpressure of the arch is the resultant. In this manner the horizontal andvertical thrust are taken care of and the necessity for building suchmassive abutments as heretofore is avoided.

In the drawings, 10 is an arch of any approved construction. t I

11 is the fill in back of thearch composed of soil or any suitablematerial. The arrow 12 indicates the direction of the line of pressurein Fig. 1, and the similar arrow 13 indicates the same line in Fig. 2.

' Adjacent to the arch and in a substantially horizontal position isarranged a plate or member 20, composed of any suitable materialas, forinstance, stone similar to the material of which the arch itself iscomposed. This plate 20 is laid upon the portion of the soil 111immediately beneath it, and the fill is placed over it so as to coverit. It must be made of suflicient depth to be strong enough to resistthe weight of the fill above it, and it should be as wide as may befound necessary up to the width of the arch. The plate may also be madetapering slightly toward its extremity or edge 21 away from the arch inorder to increase the friction between it and the materials on each sideof it, so as to assist in resisting the horizontal thrust, or it may bemade with an expanded extremity 22, as shown in Fig. 2, for the samepurpose. At an angle to the member 20 is shown the second member 30 ofthe abutment. This may be made integral with the end of the arch, asshown in Fig. 1, or simply embedded therein or adjacent to it, as shownin Fig. 2. It should be sufficiently large in size to reach with itsfoundations into firm soil and should be arranged so as to take thevertical or downward thrust ofthe arch, In Fig. 2 it is shown made oftwo long piles 31 and 32, while in Fig. 1 it is simply a mass ofmasonry. In

Fig. 1 the axis 3 of the mass is vertical, while in Fig. 2 the axes ofthe piles (which together are the equivalent of a mass of masonry) areat an acute angle with the longitudinal plate 20'and yet do'notsufficiently depart from a vertical line to defeat their purpose ofresisting the downward thrust.

The plate 20 does not need any foundation,

since a verticalmovement, due to settling, may occur in'it, or it mayeven be ruptured without loss of the function of resisting horizontalpressure. This plate should be placed at such a height that it shouldmeet the arch where the line of pressure reaches the confines of. thelatter.

In Fig. 1 there is shown a cofi'er-dam or cribwork L0, adapted toconfine the vertical member of the abutment 30. This construction isuseful where the soil is of a loose and yielding nature.

My invention has great practical advantages. It is much cheaper than themethod of building ordinary masonry abutments in one piece, because iteffects a saving in excavation and masonry. It also enables an arch tobe built closer to existing buildings, as the plate 20 may frequently beplaced above the foundations of such buildings and yet be at the properplace to accomplish its desired functions. In existing arches, moreover,where the abutments are insufficient to resist the horizontal thrust andthere is a tendency to rupture this horizontal plate 20 may be insertedand such destructive tendency checked.

What I claim as new is 1. An abutment member for arches, consisting of aplate placed ina substantially horizontal position in contact with theend of the arch adjacent to its pressure-line.

2. An abutment for arches, comprising two members, one horizontal andadapted to resistthe thrust in that direction, and one vertical andadapted to resist the thrust in that direction.

3. An abutment for arches, comprising two members, one horizontal andadapted to resist the thrust in that direction, and one vertical andadapted to resist the thrust in that direction, the two members beingeach adjacent to the termination of the pressure-line of the arch.

4. An abutment for arches, comprising two members, each placed incontact with the end of the arch near its pressure-line, one memberbeing substantially horizontal and the other member being at an anglethereto and adapted together to resist the pressure of the arch.

5. An abutment for arches, comprising two members, each arranged at theend of the arch, one arranged substantially horizontal and the other atan angle thereto whereby their respective axes are in lines of which theline of pressure of the arch is the resultant.

In witness whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

MAX MoLLER.

Witnesses:

HEINR. FRANZ SCHMITZMANEY, WILHELM LEHRKE.

